Zepp is short form for Zeppelin and is a resonant antenna end fed by a ladder line. The name comes from Zeppelin which was a type of rigid airship named after the German inventor Ferdinand von Zeppelin. Zeppelin antennas were wire antennas that could be trailed behind the Zeppelin airship. As they were trailed antennas they were used in end fed configuration. Double Zepp is a center fed half wavelength antenna. Double extended Zepp antenna consists of two collinear 0.64 wavelength elements fed in phase. It has a gain of 3 dB over a dipole along the main lobe which is perpendicular to the direction of the elements.
